dualteq.m

多载波调制的仿真程序

   selectSubs = usedSubs;
   
   %calculate SNRs and usable channels
   [subMFBall,subMFB,noiseSpec,channelGain,inputSpec] = ...
   calcsnrs_dual(inputSpecAll,channelGainAll,noiseSpecAll,gamma,usedSubs);

   % chose method and design TEQ
   [B, W, D, MSE, Dv, I,title_str] = selmeth_dual(method,inputSignal,...
      receivedSignal,noise,channel(1:N),...
   Nb,Nw,Dmin,Dmax,barflag,N,numIter,inputSpec,noiseSpec,channelGain,...
   selectSubs,gamma);

   % get performance results
   [SSNR, SNR, subSNR,geoSNRfinal,geoSNRmfb,bDMTfinal,bDMTmfb,...
         RDMTfinal,RDMTmfb,hw,Fh,Fw,colorNoiseaft,Fhw] = ...
      perform(W,B,channel,D,Nb,N,inputSignal,noise,...
      channelGainAll,inputSpecAll,noiseSpecAll,margin,codingGain,fs,subMFBall,usedSubs);
   
  % save resuls to disk in order to use it in other functions 
   save tmpresults title_str N hw B D Nb W Nw subSNR subMFB channel Fh ...
	   noiseSpec colorNoiseaft Dv Dmin Dmax Fhw Fw usedSubs ... 
       inputSignal receivedSignal noise;
   
   %Second pass for sub-bandwidth teq design
   selectSubs = [CdualMin:CdualMax]';
   
   % chose method and design the second TEQ
   [B2, W2, D2, MSE2, Dv2, I2,title_str2] = selmeth_dual(method,inputSignal,...
      receivedSignal,noise,channel(1:N),...
   Nb,Nw,Dmin,Dmax,barflag,N,numIter,inputSpec,noiseSpec,channelGain,...
   selectSubs,gamma);

   % get performance results
   [SSNR2, SNR2, subSNR2,geoSNRfinal2,geoSNRmfb2,bDMTfinal2,bDMTmfb2,...
         RDMTfinal2,RDMTmfb2,hw2,Fh2,Fw2,colorNoiseaft2,Fhw2] = ...
      perform(W2,B2,channel,D2,Nb,N,inputSignal,noise,...
      channelGainAll,inputSpecAll,noiseSpecAll,margin,codingGain,fs,subMFBall,usedSubs);
  
    save tmpresults2 B2 W2 D2 MSE2 Dv2 I2 title_str2 SSNR2 SNR2 ...
    subSNR2 geoSNRfinal2 geoSNRmfb2 bDMTfinal2 bDMTmfb2 ...
    RDMTfinal2 RDMTmfb2 hw2 Fh2 Fw2 colorNoiseaft2 Fhw2;
    
   %get Dual-path TEQ design
   dualSNR=subSNR; 
   for i=1:length(subSNR)
       if subSNR(i)<subSNR2(i)
           dualSNR(i)=subSNR2(i);
       end
   end
   
   [geoSNRdual bDMTdual RDMTdual] = geosnr(dualSNR(usedSubs),margin,codingGain,N,Nb,fs);
   
     % put results into table
   str = sprintf('%1.3fe6',RDMTfinal/1e6);
   set(methRateHndl,'string',str);
   str = sprintf('%1.3fe6',RDMTfinal2/1e6);
   set(methSNRHndl,'string',str);
   str = sprintf('%1.3fe6',RDMTdual/1e6);
   set(methSSNRHndl,'string',str);
   str = sprintf('%3.1f',SSNR);
   set(methDelayHndl,'string',str);
   str = sprintf('%3.1f',SSNR2);
   set(methMSEHndl,'string',str);
   str = sprintf('%1.3fe6',RDMTmfb/1e6);
   set(methMaxHndl,'string',str);
   
   TEQequalizerTaps = W;
   TEQtargetImpulseResp = B;
   TEQoptimalDelay = D;
   TEQoriginalChannel = channel;
   TEQequalizedChannel = hw;
   TEQmatchedFilterBoundPerChannel = subMFB;
   TEQSNRperChannel = subSNR;
   TEQoriginalChannelFreqResp = Fh;
   TEQequalizerFreqResp = Fw;
   TEQequalizedChannelFreqResp = Fhw;
   TEQchanNoisePowSpecAfterEqual = colorNoiseaft;
   TEQchanNoisePowSpecBeforeEqual = noiseSpec;
   TEQperformanceVersusDelay = Dv;
   TEQDmin = Dmin;
   TEQDmax = Dmax;
   TEQNb = Nb;
   TEQNw = Nw;
   TEQN = N;
   
   save teqresults TEQequalizerTaps TEQtargetImpulseResp  ...
	   TEQoptimalDelay TEQoriginalChannel TEQequalizedChannel ...
	   TEQmatchedFilterBoundPerChannel TEQSNRperChannel ...
	   TEQoriginalChannelFreqResp TEQequalizerFreqResp ...
	   TEQequalizedChannelFreqResp TEQchanNoisePowSpecAfterEqual...
	   TEQchanNoisePowSpecBeforeEqual TEQDmin TEQDmax TEQNb TEQNw TEQN;
	   
   % plot result
   dualteq('plotGraph');
   set(gcf,'Pointer','arrow');
   return
   
   % plot graph
elseif strcmp(action,'plotGraph'),
  legend off
  set(gcf,'Pointer','watch');
   % get handles
   fhndlList = get(gcf,'Userdata');
   viewHndl = fhndlList(12);
   freqzHndl = fhndlList(1);
   % set axis
   axHndl = gca;
   axes(freqzHndl);
   % which graph is going to be ploted
   graphNum = get(viewHndl,'value'); 
   %1= TIR/SIR, 2= TEQ impulse res., 3= TEQ freq. res., 4= SNR/MFB
   %5=original and short channel impulse res, 6 = noise power spec., 
   %7= delay plot, 8= equalized channel freq
   
   % load results for current TEQ
   load tmpresults;
   load tmpresults2;
   freqAxis = 1:N/2+1;
   
   % plot chosen graph
   if graphNum == 1
      legend off
      plot(freqAxis(usedSubs),10*log10(subSNR(usedSubs)+eps))
      hold on;
      plot(freqAxis(usedSubs),10*log10(subSNR2(usedSubs)+eps),'g')
      plot(freqAxis(usedSubs),10*log10(subMFB(usedSubs)+eps),'r')
      hold off
      grid on
      axisSet = axis;
      axisSet(1) = min(freqAxis(usedSubs))-2;
      axisSet(2) = max(freqAxis(usedSubs))+2;
      axis(axisSet);
      xlabel('frequency')
      ylabel('magnitude (dB)')
      title([title_str,' achieved and upper-bound SNR'])
      legend('SNR1','SNR2','MFB',0);
      
   elseif graphNum == 2      
 	  legend off
      hw100 = hw(1:100)/norm(hw);
      axhndlList = get(freqzHndl,'UserData');
      hndl = plot(hw100); 
      hold on; 
      plot(D+1:D+Nb,B,'r','linewidth',2); hold off;
      set(gcf,'handlevisibility','callback')
      grid on
      xlabel('tap number')
      ylabel('amplitude')
      title([title_str,' TIR and SIR'])
      legend('SIR','TIR');
      
   elseif graphNum == 3
      legend off
      hndl = stem(W); 
      if Nw > 3
         hold on;
         plot(W,':');
         hold off
      end
      axis([0 Nw+1 1.1*min(W)*(min(W)<=0) 1.1*max(W)*(max(W)>0)])
      xlabel('tap number')
      ylabel('amplitude')
      title([title_str,' TEQ impulse response'])
      
   elseif graphNum == 4
      legend off
      plot(freqAxis(usedSubs),20*log10(abs(Fw(usedSubs))+eps));
      grid on
      axisSet = axis;
      axisSet(1) = min(freqAxis(usedSubs))-2;
      axisSet(2) = max(freqAxis(usedSubs))+2;
      axis(axisSet);
      xlabel('frequency bin number')
      ylabel('magnitude (dB)')
      title([title_str,' TEQ frequency response'])
      
   elseif graphNum == 5
      legend off
      maxAmp = max(abs(hw));
      plot(channel(1:500)/max(abs(channel))*maxAmp);
      hold on
      plot(hw(1:500),'r');
      hold off
      grid on	
      xlabel('discrete time (n)')
      ylabel('amplitude')
      title([title_str,' Original & Shortened Channel'])
      legend('original','shortened',0);         
      
   elseif graphNum == 6
      legend off
      plot(freqAxis(usedSubs),20*log10(noiseSpec(usedSubs)+eps),'r')
      hold on
      plot(freqAxis(usedSubs),20*log10(colorNoiseaft(usedSubs)+eps))
      hold off
      grid on	
      axisSet = axis;
      axisSet(1) = min(freqAxis(usedSubs))-2;
      axisSet(2) = max(freqAxis(usedSubs))+2;
      axis(axisSet);
      xlabel('frequency')
      ylabel('magnitude (dB)')
      title([title_str,' Noise Power Spectrum'])
      legend('before TEQ','after TEQ',0);         
      
   elseif graphNum == 7
      legend off
      plot(Dmin:Dmax,10*log10(real(Dv(Dmin:Dmax))+eps))
      grid on	
      ylabel('objective function (e.g. MSE for MMSE method)')
      xlabel('delay')
      title([title_str,' Cost vs delay plot'])
      
   elseif graphNum == 8
      legend off
      plot(freqAxis(usedSubs),10*log10(abs(Fhw(usedSubs)).^2+eps));
      grid on
      axisSet = axis;
      axisSet(1) = min(freqAxis(usedSubs))-2;
      axisSet(2) = max(freqAxis(usedSubs))+2;
      axis(axisSet);
      ylabel('magnitude (dB)')
      xlabel('frequency')
      title([title_str,' Equalized Channel Frequency Response'])
 
  elseif graphNum == 9
      legend off
      plot(freqAxis(usedSubs),10*log10(subSNR2(usedSubs)+eps))
      hold on;
      plot(freqAxis(usedSubs),10*log10(subMFB(usedSubs)+eps),'r')
      hold off
      grid on
      axisSet = axis;
      axisSet(1) = min(freqAxis(usedSubs))-2;
      axisSet(2) = max(freqAxis(usedSubs))+2;
      axis(axisSet);
      xlabel('frequency')
      ylabel('magnitude (dB)')
      title([title_str,' achieved and upper-bound SNR for second TEQ'])
      legend('SNR','MFB',0);
  end
  
   set(gcf,'Pointer','arrow');
   return
   
   % get help
   elseif strcmp(action,'info'),
   ttlStr = get(gcf,'name');
   myFig = gcf;
   
   topic1 =  ['Dual-path TEQ design demo'];
   helptop1 = [...
     'This demo lets you design Dual-path TEQ and analyze its performance.  '
     '                                                                      '
     'Usage: Set parameters to desired values and hit the Calculate button. '
     '                                                                      '
     'The following design methods are supported:                           '
	 '  Maximum channel capacity method,                                    '
     '  Minimum intersymbol interference method,                            '
     ];
   
   topic2 =  ['Design and Simulation Paramters'];
   helptop2 = [...
	 'On the top of the control window on the right is a pulldown menu      '
     'from which a design method can be chosen.                             '
	 'Below this pulldown menu are the following editable text windows      '
     'which are used to set the desired parameters,                         '
     '  Shortened impulse response (SIR) length. This is the desired length '
     '   of the channel after equalization. For example, it should be set   '
     '   to 33 (one plus the cyclic prefix length) for the ADSL standard.   '
     '  Time domain equalizer (TEQ) length. Defines the number of taps of   ' 
	 '   the TEQ.                                                           '
     '  Fast Fourier transform (FFT) size. Sets the FFT size used in DMT    '
     '   modulation. It is twice the number of subchannels.                 '
     '  Coding gain (dB). Defines a coding in dB used during capacity       '
     '   calculations.                                                      '
     '  Margin (dB). Sets the desired system margin in dB. This is also     '
     '   used in capacity calculations.                                     '
     '  Dmin and Dmax. The optimal delay is search in the interval between  '
     '   Dmin and Dmax.                                                     '
	 '  Input power (dBm). Defines the input signal power in dBm.           '
	 '  AWGN pow (dBm/Hz). Sets the amount of additive white Gaussian noise '
     '   in dBm/Hz. AWGN is added to the near-end crosstalk noise.          '
     '  CSA loop \# (1-8). Selects the desired channel to run the simulation'
     '   on. Currently 8 standard CSA loops are supported.                  '
     '                                                                      '
     '  On the bottom of the control window on the left there are other     '
     '  editable text windows which can be used to set the desired          '
     '  parameters:                                                         '
     '  Umin and Umax: Sets the used subcarriers for the first TEQ with the '
     '                 index started from Umin to Umax.                     '
     '  Cmin and Cmax: Sets the selected subcarriers for the second TEQ with'
     '                 index started from Cmin to Cmax.                     '];
   
     topic3 =  ['Graphics'];
   helptop3 = [...
	 'Below the editable text windows is another pull-down menu which       '
     'is used to select the desired graph to be displayed.                  '
     'The following graphics can be selected:                               '
     '  SNR & MFB. The SNR for first and second TEQ and matched filter bound'
     '  to the SNR is displayed as a function of frequency (subchannels).   '
     '  Noise Power Spectrum. Shows the power spectrum of the noise which   '
     '   consists of NEXT noise plus AWGN.                                  '
     '  The rest plots display the result from the first TEQ.               '
     '  Target & shortened channel. Displays the shortened channel impulse  '	 
	 '   response and the target channel impulse response for the MMSE and  ' 
	 '   geometric SNR methods. For all other methods the location of the   ' 
     '   target window is displayed instead of a target impulse response.   '
     '  TEQ impulse response. Shows the impulse response of the TEQ.        '
     '  TEQ frequency response. Shows the TEQ in frequency domain.          '
     '  Original & shortened channel. Displays the channel impulse response '
     '   before and after equalization.                                     '
     '  Delay Plot. Displays the performance measure of the method with     '
     '   respect to the delay.                                              '
     '  Equalized channel freq resp. Displays the frequency response of the '
     '   channel after equalization.                                        '];
 
   topic4 =  ['Performance Measures'];
   helptop4 = [...
'The two remaining buttons in the control frame are                    '
'   Info. Displays this help.                                          '
'   Calculate. Starts the calculation and performance evaluation of the'
'    TEQ.                                                              '
'The following performance measures are calculated and listed in the   '
'table:                                                                '
'   Rate1. Gives the achievable bit rate with the given channel and the' 
'          first TEQ settings.                                         '
'   Rate2. Gives the achievable bit rate with the given channel and the' 
'          second TEQ settings.                                        '
'   Ratedual. Gives the achievable bit rate with the given channel and ' 
'          the dual-path TEQ settings.                                 '
'   SSNR1. Shows the shortening SNR in dB for the first TEQ. This is   '
'   defined as the ratio of the energy of the shortened channel impulse'
'   response in the target window the the energy outside the target    '
'   window.                                                            '
'   SSNR2. Shows the shortening SNR in dB for the second TEQ.          '
'   Max Rate. Shows the absolute maximum achievable bit rate given the '
'    channel and equalizer settings. It is basically the capacity      '
'   calculated from the MFB.                                           '];
		 
   str =  { topic1 helptop1; topic2 helptop2; topic3 helptop3; topic4 helptop4 };
   
   helpwin(str,'Topic 1','Dual-path TEQ design demo')                   
   return  
   
else
   disp(sprintf( 'Internal ERROR: ''%s'' not recognized',action))
end